The flowability of (co)polycarbonate compositions or (co)polycarbonate blends can be increased by the addition of low molecular weight compounds. Since substances of this kind, however, simultaneously act as plasticizers, they lower the heat distortion resistance and glass transition temperature of the polymer matrix. This in turn is undesirable, since this reduces the temperature use range of the materials.
DE 102004020673 A1 describes copolycarbonates having improved flowability, based on bisphenols having an ether or thioether linkage.
DE 3918406 A1 discloses blends for optical data storage means, based on a specific polycarbonate with elastomers or other thermoplastics, and the use thereof in optical applications, specifically optical data storage means such as compact discs.
EP 0 953 605 A2 describes linear polycarbonate compositions having improved flow characteristics, characterized in that cyclic oligocarbonates are added in large amounts, for example 0.5% to 4%, and are homogenized in the matrix of a linear BPA polycarbonate at 285° C. by means of a twin-shaft extruder. In the course of this, the flowability increases as the amount of cyclic oligocarbonates rises. At the same time, however, there is a distinct decrease in the glass transition temperature and hence the heat distortion resistance. This is undesirable in the industrial applications of (co)polycarbonate compositions having relatively high heat distortion resistance. This disadvantage then has to be compensated for through the use of higher amounts of costly co-bisphenols.